21453734250 has 256 divisors, whose sum is σ = 64691827200. Its totient is φ = 5230137600.

The previous prime is 21453734249. The next prime is 21453734287. The reversal of 21453734250 is 5243735412.

21453734250 is a `hidden beast` number, since 214 + 53 + 7 + 342 + 50 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 9563629 + ... + 9565871.

It is an arithmetic number, because the mean of its divisors is an integer number (252702450).

Almost surely, 2^21453734250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21453734250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32345913600).

21453734250 is an abundant number, since it is smaller than the sum of its proper divisors (43238092950).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21453734250 is a wasteful number, since it uses less digits than its factorization.

21453734250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2391 (or 2375 counting only the distinct ones).

The product of its (nonzero) digits is 100800, while the sum is 36.

The spelling of 21453734250 in words is "twenty-one billion, four hundred fifty-three million, seven hundred thirty-four thousand, two hundred fifty".